5 reasons why a householder prefer to oversizing Solar Array

Date: 06/25Viewed (2668)

When
considering to install a on grid solar power system, most householders are
suggested to make the PV array capacity bigger than the capacity of solar
inverter. For example,in a system with 6kW solar panels,usually it would
be configured with a 5kW solar inverter.

Oversizing a
PV array, also referred to as undersizing a PV inverter, It can be a valuable
tool for system designers seeking to deliver a maximum amount of energy at a
lowest possible specific cost.

1.Smaller
delivered energy than rated output power

Not all DC
array output is translated into useful AC energy. There are several losses
along the way such as cable losses, inverter efficiency losses, etc.

2.Falling
cost of solar panels

Solar
panels’s prices have fallen drastically, therefore the incremental cost of the
DC side of the system has significantly decreased. This way, one can allow
clipping of power at peak generation time in order to maximize generation
during non-peak hours.

3.Rated
module capacity against actual capacity

Solar panels
often operate below the nominal rated power. Nominal rated power is the output
of the module, however, these conditions are not always met under standard test
conditions. Inverter efficiency is low when it operates at low power levels, so
you might be better suited with a smaller inverter. Also because the output of
the solar panels will decrease slightly over the lifetime of the panels, the
smaller inverter will operate more efficiently than a large one once the panel
output begins to decrease

Modules are
rated at STC conditions, which rarely occur in actual on-site conditions.
Secondly, modules are sensitive to temperature and soiling. Both these factors
tend to decrease module output. There may be very few instances when the
modules are operating at their peak power output. This results in gross
under-utilization of the inverter’s capacity. Modules also tend to degrade over
time – which means that the peak power levels may never be attained after a few
years of operation. In such cases, it would make sense to increase the energy
production by oversizing the inverters.

4.Financial
Considerations

Oversizing inverters can increase
production of energy during non-clipping (non-peak) times. This results in a
greater yield – and therefore greater revenues. What’s more, and ‘Time of Day’
incentives may skew economics towards production during non-peak times and
designers may want to make best use of this.

Inverters
sometimes need to be installed in specific locations, either due to constraints
from the owner or local electrical regulations. This may mean it would not be
possible to install as many inverters at a site as would be desired for a
perfectly sized system. However by oversizing PV arrays, it may be possible to
achieve almost the same annual energy output with fewer installed inverters.